phpbb 3.0.12 problem?

hi i am getting this error after moving common.php into the forum foldrer:

[phpBB Debug] PHP Warning: in file [ROOT]/common.php on line 127: file_exists(): open_basedir restriction in effect. File(/var/www/clients/client4/web9/web/../wordpress/wp-blog-header.php) is not within the allowed path(s): (/var/www/clients/client4/web9/web:/var/www/clients/client4/web9/private:/var/www/clients/client4/web9/tmp:/var/www/domainname/web:/srv/www/domainname/web:/usr/share/php5:/usr/share/php:/tmp:/usr/share/phpmyadmin:/etc/phpmyadmin:/var/lib/phpmyadmin:/usr/share/php)

any ideas?

http://wordpress.org/plugins/phpbb-single-sign-on/